animals Article Large Lemurs: Ecological, Demographic and Environmental Risk Factors for Weight Gain in Captivity Emma L. Mellor 1,* , Innes C. Cuthill 2, Christoph Schwitzer 3, Georgia J. Mason 4 and Michael Mendl 1 1 Bristol Veterinary School, University of Bristol, Langford House, Langford, Bristol BS40 5DU, UK;
[email protected] 2 School of Biological Sciences, University of Bristol, Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TQ, UK;
[email protected] 3 Dublin Zoo, Phoenix Park, Dublin 8, D08 WF88, Ireland;
[email protected] 4 Department of Animal Biosciences, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada;
[email protected] * Correspondence:
[email protected] Received: 29 June 2020; Accepted: 12 August 2020; Published: 18 August 2020 Simple Summary: Excessive body mass, i.e., being overweight or obese, is a health concern. Some lemur species are prone to extreme weight gain in captivity, yet for others a healthy body condition is typical. The first aim of our study was to examine possible ecological explanations for these species’ differences in susceptibility to captive weight gain across 13 lemur species. Our second aim was to explore demographic and environmental risk factors across individuals from the four best-sampled species. We found a potential ecological explanation for susceptibility to captive weight gain: being adapted to unpredictable wild food resources. Additionally, we also revealed one environmental and four demographic risk factors, e.g., increasing age and, for males, being housed with only fixed climbing structures. Our results indicate targeted practical ways to help address weight issues in affected animals, e.g., by highlighting at-risk species for whom extra care should be taken when designing diets; and by providing a mixture of flexible and fixed climbing structures within enclosures.